TAMPA — Life in the NFL has made a new man of Tampa Bay Buccaneers rookie defensive tackle Akeem Spence.

Once a burger-and-fries kind of guy, the 6-foot-1, 307-pound Spence has started to eat more fish and greens in recent weeks, but it’s not just Spence’s dietary habits that have changed.

Spence has also taken some steps to better care for his body that he never dreamed he’d take when he came into the league as a fourth-round pick out of Illinois in April.

“I’ve taken it upon myself to do things such as getting massages and even getting pedicures for my feet,” Spence said. “You can’t believe how great a pedicure can make you feel.”

Spence said he first started making the changes around Week 8 of the season, when he started feeling the effects of not just the intense workouts he participates in each day, but also the punishment his body takes on game days.

“I was struggling and my body was feeling like, ugh,” Spence said. “Once everything started aching, I just had to do it. So I started using the (hot and cold) tubs more and making some other changes.”

The most drastic change, Spence said, was dietary. Spence said he grew up hating salads of all kinds, but has grown to be a big fan of Caesar and Spanish salads.

“Before, you couldn’t get me to eat a salad,” Spence said. “I thought it was the worst thing ever. But since I’ve added more greens to my diet, I’ve kind of gotten hooked on those Caesar and Spanish salads.”

Money ball: Bucs coach Greg Schiano said Thursday the ability to convert third downs will go a long way toward deciding the winner of Sunday’s game against the 49ers. That doesn’t bode well for the Bucs.

The Bucs this year have converted only 33.2 percent of their third downs, which ranks 31st in the 32-team league, and they’ve done an even worse job in that area while winning four of their last five games.

The Bucs have converted only 20.8 percent (15 of 72) of the third downs they’ve faced the last five games, and they’ll have a hard time improving on that percentage against San Francisco.

The 49ers, who are ranked fourth overall in the league in total defense, will go into Sunday’s game tied for third in the league with a 34.4 conversion rate on third down.

“When you have tough defenses, third down is where they really shine,’’ Schiano said. “That’s the money down, and they have the guys to do it. You’re looking at one Pro Bowler after another staring you in the face.

“But we have to convert more. Last week we had, not a lot of drops but one or two, on third down and we had some pressure (against us). So that’s going to be huge. You ask, what are the keys, third down is a big one for them and us.’’

Inside information: The Bucs are using all the resources available to them in their attempt to gain an edge on the 49ers and that includes probing the mind of former San Francisco S Dashon Goldson for tips on the 49ers’ tendencies.

“He’s helped us a lot this week, both on the field and up in the meeting rooms,’’ Schiano said of Goldson, who spent his entire career with the 49ers before joining the Bucs as a free agent last offseason.

“Dashon has been great; he’s been giving us everything he’s got,’’ CB Darrelle Revis said. “He’s been spilling the beans and we definitely appreciate that. We’re going to need it.’’

Proud papa: As the senior linebacker on the Bucs roster, Adam Hayward has had a hand in the development of second-year starter Lavonte David. Hayward says David’s emergence this year has made him proud of the contribution he’s made.

“It’s like being a step-parent and you finally see the light go on in your stepchild’s eyes,” Hayward said. “I’m always coaching him up and when he finally listens and makes big pays, I feel like a proud parent, because he’s like a son to me.’’